Thousands of microscopic white dots are moving all over the place in my tank. My Betta and snail don't seem to care at all as they are both eating and acting okay. Also, I have been unable to spot any on their bodies. These things are so small that if you take one step back they will disappear. What's going on here?

Ugh I put 5 algae wafers in my tank for the snails during Christmas break and when I came back two weeks later my tank was over run with these things. Grossed me out. XD. But I used the gravel filter to vacuum up all the bits of leftover algae wafers, vacuuming up 2 gallons every day for 5 days and my tank is now planarian free. :)

Ugh I put 5 algae wafers in my tank for the snails during Christmas break and when I came back two weeks later my tank was over run with these things. Grossed me out. XD. But I used the gravel filter to vacuum up all the bits of leftover algae wafers, vacuuming up 2 gallons every day for 5 days and my tank is now planarian free. :)

Yep. After vacuuming I noticed they are concentrated only on the glass above a rotting piece of algae wafer I missed. Also I read they are completely harmless but are an indicator that my water is not harmless.